it will expect a Makefile to have been created, and run Make against it, at install time. You can also list @gemspec.extensions = 'ext/mkrf_conf.rb'@ and it will run that, expect a Rakefile to have been created, and run rake against it.

yard gem has a way to create yard docu after installing a gem (instead of the default rdoc).

gem_file_conflict_checker gem: warns you when you install two gems whose lib files collide (which can cause serious problems, and is common for gem developers who install their own versions of gems, etc.)